Electrical contactor



INVENTOR. ULE W. NE L SUN H/xS' ATTORNEY l l //-"l I l l l l I 0. W. NELSON ELECTRICAL CONTACTOR Flled March 21 1942 Feb. 23, 1943.

Patented Feb. 23, 1943 UNITED STATES} PATENT OFFICE 2,311,855 ELECTRICAL CONTACTOR Ole W. Nelson, Detroit, Mich. Application March 21, 1942, Serial No. 435,731

Claims.

My invention pertains to a circuit maker and breaker and more particularly to an inclination and vibration responsive device for operating electrical signals or controls.

It is an object of my invention to provide an inclination or vibration responsive electrical circuit maker and breaker of a simple rugged construction which is reliable and positive in operation.

It is also an object of my invention to provide an inclination or vibration responsive electrical contactor which is conveniently adjustable either to vary the force with which the contacts will be closed by a predetermined vibration or inclination or to vary the amplitude or amount of vibration or inclination to which the device will respond.

It is a further object of my invention to provide an inclination or vibration responsive circuit maker and breaker comprising a metal pendulum element conformed to provide an electrical contact at one end and a weight portion at the other end, universal pivot means supporting the pendulum at a selectable position intermediately of its ends and a stationary electrical contact dis posed for engaging the contact end of the pendulum in any of its adjusted operating positions and from a predetermined or adjustable amount of clearance therebetween.

Further objects and advantages are within the scope of my invention, such as relate to the arrangement, operation and function of the related elements of the structure, to various details of construction and to combinations of parts, elements per se, and to economics of manufacture and numerous other features as will be apparent from a consideration of the specification in conjunction with the drawing disclosing specific embodiments of my invention, similar reference characters being applied to corresponding elements throughout, and in which:

Fig. 1 is a side elevational view of my improved inclination and vibration responsive circuit maker and breaker;

Fig. 2 is a plan view thereof;

Fig. 3 is a cross sectional view on line 33 of Fig. 1;

Fig. 4 is a fragmentary side elevational view showing a different modification of the cooperatively engageable electrical contacts; and

Fig. 5 is a side elevational view showing a universally mounted housing suitable for enclosing and supporting my improved electrical contactor in certain installations.

Referring more specifically to Figs. 1, 2 and 3 of the drawing, my improved inclination and vibration responsive electrical circuit maker and breaker comprises a frame structure having two side pieces H and a bottom cross-piece I3 of metal which may be conveniently made from separate parts or a single strip of metal bent to a substantially flat bottomed U shape. The upper side of the frame is closed by an upper cross-piece l5 which is made of any suitable electrical insulation material, such as a phenolic condensation product, for example. The upper ends of the side pieces are turned inwardly to provide lugs I! to which the upper insulating cross-piece 15 may be secured by rivets 19, or any suitable fastening means. At one side an electrical contact plate 2| may be secured on the lug ll of one of the side pieces by the rivets IS in electrically conducive contact therewith and having one end projecting laterally. The eX- tending end of the contact plate 2| is preferably provided with an aperture 23 to facilitate inserting a wire (not shown) to be soldered thereto for a good low resistance connection, or a suitable binding post (not shown) may be mounted thereon, as will be readily understood.

A micrometer adjusting screw 25 passes threadably through a bushing 2'! in an aperture in a central portion of the insulating upper cross-piece l5 for supporting a stationary electrical contact 28 adjustably in the space enclosed by the frame. The frame supported electrical contact 28 is made of any desirable metal such as tungsten, silver or any suitable metal commonly used on delicate electrical instruments and relays to provide low resistance contact. A contact connection plate 29 is provided on the upper cross-piece whereon it is clamped by a nut 3| which screws down on the upper end of the bushing 2'! in order to provide electrical connection with the micrometer screw 25. One end of the contact plate 29 is provided with a connection lug 33 extending laterally therefrom and having an aperture 35 wherein a circuit wire may be inserted and soldered, or a suitable binding post terminal (not shown) may be mounted therein. A knurled knob 31 is provided on the upper end of the threaded shaft or micrometer screw to facilitate adjusting the stationary contact 28 very precisely to any desired position within the frame enclosure. A lock-nut 39 is provided on the micrometer screw to be turned down to firmly lock the screw and the contact 28 in the desired adjusted position.

A metallic pendulum element 4| is provided which is suitably conformed at the lower end to provide a weight 43 and at the upper end to provide an electrical contact 45. The intermediate portion 4| of the pendulum is preferably a threaded shaft which is adjustably mounted threadably in an aperture in the middle of a transverse pivot shaft 46 (shown in Fig. 3) wherein it is conveniently raised or lowered to any adjusted position and secured by a lock nut 41. The ends of the transverse pivot shaft 46 are provided with conical apertures to receive the tapered points 48 of pivot screws 49 which pass inwardly through the sides of a universal mounting member The pivot screws 49 are disposed in threaded apertures in alignment in opposite sides of the supporting member 51 which may be a circular ring or which may also be of a non-circular shape.- The screws 49 may be suitably adjusted to eliminate side play and slack motionwhile permitting the shaft 46 and the pendulum to oscillate freely in response to the slightest inclination, vibration or other motion, and if desired these may be secured by lock nuts (not shown). To provide low resistance electrical connection at all times between the metallic pendulum element and the supporting ring or member, any suitable flexible low resistance connection therebetween may be provided. For example, I have shown a pig tail connection 53 which may comprise any piece of conductor of suitable flexibility, secured as by soldering one end to the shaft 46 and the other end may be attached firmly and electrically connected to the universal supporting member 5| as by screw 55, removable to facilitate removal of the shaft. The intermediate portion of the flexible pig tail conductor 53 is preferably provided with considerable slack which may be disposed in a spiral formation to minimize interference with the oscillations of the pendulum element. This may also be a balancing spring.

The universal support member or ring 5| is provided on opposite sides with pivot shafts 56 projecting outwardly in aligned diametrical relation at right angles to the diameter whereon the two pivot screws 49 are aligned. The outer ends of the two pivot shafts 56 are each provided with a conical bearing aperture for receiving the tapered points 51 of two pivot screws 59 which screw inwardly through the side pieces H of the frame. By properly adjusting the pivot screws 59, the pivot shafts 56 may be journalled for free oscillatory movement with a minimum of slack motion and then the pivot screws are locked in adjusted positions by turning the lock nuts 60 firmly thereon, as will be understood. To provide a low resistance electrical connection at all times between the metal frame and the support ring, either one of the pivot shafts 55 is provided with a pig tail connection 53 which connects to the frame side piece II where one end is secured as by a screw 55, the other end being soldered to the shaft 56, as previously described with reference to the transverse pivot shaft.

The electrical contact 45 on the upper end of the pendulum element 4| may be integral therewith, although it is preferably a separate element soldered o-r brazed thereto and selected of special noncorrodible contact metal suitable for providing low resistance contact with light pressure similarly to the upper contact which it cooperatively engages. The adjacently disposed and engageable surfaces of the two electrical contact 28 and 45 may be fiat surfaces which are disposed in a parallel relation when the instrument is properly adjusted, as shown in Fig. 1. v

To vary the force with which the contacts will be engaged by a predetermined inclination or vibration, the leverage on the contact 28 is varied by varying the relation of the parts of the pendulum shaft 4| below and above the pivot shaft 45. Also by releasing the lock nut 39 the micrometer screw 25 is turned to move the upper contact 28 to approach the pendulum contact as closely as desired to provide the sensitiveness necessary for the particular installation.

In this manner my improved inclination and vibration responsive electrical contactor device may be adjusted for many different uses and applications, and after adjustment the upper contact is stationary in the frame and the pendulum contact moves relative thereto. For example, the device may be installed on an automobile and by adjusting properly for the level of the ground when the car is parked the instrument may be set so that it will operate any suitable alarm or signal if the car is moved or disturbed. In such an installation it may be desired to ob tain response only if inclination of the car is changed as by jacking up for removing a tire but not when the car is merely moved by another car striking the bumper and this may be readily accomplished by utilizing in the controlled circuit any suitable delay device of thermal or other well known types, as will be readily understood. Also the device may be mounted upon any machine or other structure and adjusted to give a Warning when the structure vibrates laterally or sways excessively. On vehicles the instrument may indicate excessive acceleration or deceleration and on ship board it may be set to indicate or give warning when the ship rolls or lists excessively. Mounted on a testing block with a firearm the device may be successively adjusted by means of the micrometer screw to provide comparative tests of different arms or ammunition. Mounted on a signal buoy my contactor device may be set to utilize the motion of the water for intermittently operating the signal. Many other uses of my improved device will be appreciated by those skilled in the art.

Fig. 4 shows a different modification of the shape of the cooperatively engageable contact surfaces. An upper or stationary contact 6| is provided having a conical aperture 63 opening downwardly, and a pendulum carried contact 6-5 is provided having a conical shaped surface 61 projecting thereinto. In this manner a very sensitive contact arrangement is provided, which is especially desirable in permanent installations but which is not so convenient for frequent adjustments as on automobiles.

Fig. 5 shows how my improved inclination and vibration device is preferably enclosed and mounted in a housing 69 which is substantially larger than the instrument in order that all the accessory elements which are electrically connected thereto may be all housed therein. The housing 69 is made of a suitable gage of sheet metal in accordance with usual practise in sheet metal to provide the desirable strength and rigidity. The entire housing 69 is supported by means of a releasable universal joint ll, of a well known construction, through which it is connected to a bracket 13 which is secured as by a bolt 15 to any structural member 11 of the automobile or machine to be protected. Such a universal clamp, which may be of any well known construction, is conveniently released by turning the knurled nut 19, and the entire housing may then be conveniently tilted first one way and then another until the desired levelled position of the instrument is obtained when, by locking the clamp, the device is prepared ready to respond to any excessive inclination or vibration movements transmitted thereto from the structure whereon it is supported. When used in certain permanent installations the instrument may be mounted upon any suitable adjustable table or platform which may be conveniently levelled.

It is apparent that within the scope of my invention, modifications and different arrangements may be made other than herein disclosed and the present disclosure is illustrative merely, the invention comprehending variations thereof.

I claim:

1. In an electrical control or signalling contactor responsive to inclination or vibration, a stationary electrical contact, a frame structure including insulating means, adjustable support means mounted on said insulating means for supporting said stationary contact at adjustable positions in the space enclosed by the frame, a metallic pendulum element suitably conformed to provide a Weighted portion at the lower end and at the upper end to provide an electrical contact suitable for engaging said stationary electrical contact, universal support means extending from the frame and connecting with said pendulum element intermediate of the ends to provide universal movement support and electrical connection therebetween, and said support means mounting the pendulum at a suitable position in said frame so that swinging movement of the pendulum may move its contact into engagement with the stationary contact.

2. In combination in an inclination or vibration responsive electrical contactor, a frame having an upper side of insulation material and the other three sides of metal, a stationary electrical contact, a metallic support passing through the insulation side of the frame and supporting said contact in the space enclosed by the frame, a metallic pendulum element suitably conformed to provide a weighted portion at the lower end and at the upper end to provide an electrical contact suitable for engaging the stationary electrical contact, universal support means extending from the frame and connecting with said pendulum element intermediate of the ends to provide electrical connection therebetween and to support the pendulum for free universal movement with its upper end contactor suitably spaced from the stationary contact to provide the desired degree of sensitivity for engagement with the stationary contactor when the pendulum moves from a normal position by a predetermined amount.

3. In an electrical contactor responsive to inclination or vibration, a frame structure having three sides of metal and an upper cross-piece of electrically insulating material, a metallic screw member passing adjustably through the upper insulating cross-piece and extending down, into the enclosed space within the frame, the lower end of said screw member having a portion suitably conformed to serve as an electrical contact, a metallic pendulum element suitably conformed to provide a weighted portion at the lower end and at the upper end to provide an electrical contact suitable for engaging the electrical contact on the lower end of said adjustable screw member, universal support means extending from the frame and connecting with said pendulum element intermediate of the ends to provide electrical connection therebetween and to support the pendulum for free universal movement suitably positioned so that the pendulum contactor is engaged with the other contact when the pendulum moves a predetermined amount from a normal position.

4. An inclination or vibration responsive circuit maker and breaker comprising, a stationary electrical contact, a frame structure having insulation means, support means adjustable in said insulation means for supporting said contact at adjustable positions in the space enclosed by the frame, a threaded pendulum shaft, a weight threadably supported on the lower end of said shaft for adjustment thereon, an electrical contact on the upper end of the pendulum shaft, a support ring, a shaft journalled diametrically within said ring, an internally threaded aperture in the central portion of said shaft supporting pendulum shaft at any desired adjusted position, pivot shafts projecting outwardly in opposite directions from said ring at right angles to said first mentioned shaft, bearing means freely supporting and journalling the outer ends of said pivot shafts on the side pieces of said frame, to support the pendulum with its contact suitably disposed for engaging the other contact when the endulum moves a predetermined distance from a normal position.

5. In an electrical control or signalling contactor responsive to inclination or vibration, a stationary electrical contact, a frame structure having an insulating member, support means adjustable on said insulating member for supporting said stationary contact at adjustable positions in the space enclosed by the frame, a metallic pendulum element suitably conformed to provide a weighted portion at the lower end and at the upper end to provide an electrical contact suitable for engaging said stationary electrical contact, universal support means extending from the frame and connecting with said pendulum element intermediate of the ends to provide universal movement support and electrical connection therebetween, said support means mounting the pendulum at a suitable position in said frame so that swinging movement of the pendulum may move its contact into engagement with the stationary contact, a housing for enclosing said frame and associated elements with any desirable control or signal means to be housed therewith, and support means for adjustably mounting said housing in any desired installation, said support means being releasable at will for universal movement to level the housing to accommodate the installation conditions and also being securable for thereafter transmitting movements or vibrations to said housing.

OLE W. NELSON. 

